Ecology, Environment and Conservation Paper

CHARACTERIZATION OF CHROMATE REDUCING PROPERTIES OF FLAVOR PROTEINS FROM PSEUDOMONAS PUTIDA AND ESCHERICHIA COLI

G. Renuga, M. Madasamy, A. Babu Thandapan and K.R. Arumugam

Abstract

Chromate (CrVI) is a serious environmental pollutant, which is amenable to bacterial bio remediation. Chromate reductase is a flavor protein that is able to reduce chromate to less soluble and less toxic Cr (III). In this work, the chromate reductase activities of two electrophoretically pure soluble bacterial flavor proteins Chr R (Pseudomonas putida) and Yie F, (Escherichia coli) were examined. Both are dimmers and chromates efficiently reduce into Cr (III). Trivalent chromium Cr (III) is insoluble, less bioavailable and less toxic. Bacterial enzymes catalyze one electron reduction of chromate, generating Cr(V), which redox cycles, generating excessive reactive oxygen species (ROS). The presence of yie F, Chr R was catalyzed chromate reduction reaction decreased ROS generation, while both enzymes are suitable for further work to improve bacterial chromate bioremediation.